1. Field of the Invention
The present invention relates to an apparatus for filling a film casing with fluid material such as raw egg separated into white and yolk, and more particularly to such a filling apparatus capable of preventing air from entering into the film casing.
2. Prior Art
Egg used a raw material for sandwiches is separated into white and yolk and is filled in a film casing 1 shown in FIG. 8 so that the egg filled in the film casing 1 is supplied in a food processing factory. The film casing 1 is formed into a cylinder by joining the opposite ends of a film made of, for example, vinylidene chloride resin at a seal portion of joined portion 1a. Raw egg is then filled into the cylinder and thereafter both ends of the cylinder filled with raw egg are clamped by clamping members 2 such as aluminum wires. Raw egg is then heated at it is filled in the film casing so that white or yolk of raw egg in the casing is hardened and then forwarded to the food processing factory. The film casing is then removed from egg in the food processing factory and egg is used as material for sandwiches.
When fluid material such as egg is filled into the film casing 1, there is a problem that air enters into the film casing 1 during the filling operation. Air entered into the film casing 1 comes to the surface of the film casing as an air bubble. Accordingly, when the filled material is white or yolk of egg, a portion of the filled egg where the air bubble exists is discolored to brown when it is heated. Since the discolored portion can be seen through the film casing, the value of the filled egg is reduced. Accordingly, when raw egg or the like is filled into the film casing, it is necessary to prevent air from entering into the film casing.
In a conventional filling operation of egg for preventing the entrance of air, only one end of a cylinder 40a formed of a film is clamped by a clamping member 2 as shown in FIG. 9 and raw egg is filled into the cylinder 40a from a filling nozzle. The cylinder 40a filled with egg is then set upright in a container 3 shown in FIG. 9 with the other end of the cylinder 40a opened and air is exhausted from the cylinder 40a. After air has been exhausted from the cylinder, the open end of the cylinder is closed tight to prevent the entrance of air and is clamped by a clamping member 2 to complete the casing 1.
However, in the above conventional operation, many processes must be made by hand and therefore the operation efficiency is very wrong.
Accordingly, it is desired to develop an apparatus which automatically fills the film casing 1 with fluid material such as egg without entrance of air. Heretofore, as an apparatus which automatically fills a cylindrical film casing with material, there has been developed an automatic filling apparatus which fills a cylindrical film casing with processed meat to manufacture sausage as shown in FIG. 10. The automatic filling apparatus is continuously fed with film 40 made of vinylidene chloride resin to roll it in a cylinder by a forming member 4 and joins the opposite ends of the rolled film by high-frequency electrodes 5a and 5b to form a cylindrical member 40a. Filling material such as processed meat is filled into the cylinder member 40a from a stuffer nozzle 6. A pair of squeezing rollers 7a and 7b are disposed under the stuffer nozzle 6 to squeeze ends of the cylindrical member 40a and the squeezed ends are clamped by a clamping member 2 formed of for example, aluminum wire. When the end of the cylindrical member 40a is squeezed by the rollers 7a and 7b, the pressure in the cylindrical member 40a is increased. However, the increase of the pressure can be adjusted by upward movement of an adjustment ring 8 slidably disposed around the stuffer nozzle 6.
However, since the conventional automatic filling apparatus as shown in FIG. 10 is used to fill the cylindrical member 40a with the material such as the processed meat which is not fluid and has a tendency that air is hard to enter into the cylindrical member together with the material, the apparatus is not quite provided with function for exhausting air from the cylindrical member 40a. Accordingly, when the apparatus is employed as a filling apparatus of fluid material such as egg as it is, much air enters into the film casing 1. Further, when the conventional automatic filling apparatus is used to fill the film casing with the fluid material, the fluid material flows out upwardly from a gap between the adjustment ring 8 and the inner surface of the film 40.